﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Demo51302
{
    class Area
    {
        public double Area1(double r)
        {
            return r * r*3.14;
        }
        public double Area1(double a, double b)
        {
            return a * b;
        }
    }
}
